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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

17112 results found.

  1. GRB050412: ROTSE-III Optical Limits
  2. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  3. GRB 050412: IR Observations
  4. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  5. GRB 050410, optical observations
  6. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  7. GRB 050410 R band Optical Observations
  8. GRB050410 : Null detection report
  9. GRB 050410, optical observations
  10. GRB050410: Radio Observations
  11. GRB 050408: Swift XRT measurement of possible jet break
  12. GRB050410: MASTER optical observations
  13. GRB 050410: Early observations with Swift-UVOT
  14. Swift-BAT detection of GRB 050410
  15. GRB 050410: Swift XRT Position
  16. GRB 050408: Properties of the Host Galaxy
  17. GRB 050408: Swift XRT analysis
  18. GRB 050408, optical observations
  19. GRB050408: REM NIR and Optical observation
  20. GRB 050408 Optical Observations
  21. GRB 050408: Optical afterglow confirmed
  22. GRB 050408, optical observations
  23. GRB 050408 optical candidate
  24. GRB 050408: Swift XRT Position
  25. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  26. GRB 050406: early Swift XRT analysis results
  27. GRB 050406 BAT refined analysis
  28. GRB 050406: Early observations with Swift-UVOT
  29. GRB 050406: Swift XRT Position
  30. Swift-BAT detection of GRB 050406
  31. Konus-Wind observation of GRB 050401
  32. GRB050401: Radio observation at 610 MHz with GMRT
  33. GRB 050401: VLT spectroscopic redshift
  34. GRB 050401 Optical Observations
  35. GRB050401: Maidanak optical observation
  36. GRB 050401 BAT refined analysis
  37. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  38. GRB 050402A: IR Observations
  39. GRB 050402: Early observations with Swift-UVOT
  40. Swift Trigger 113225: P60 Observations
  41. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  42. GRB 050401: Optical afterglow candidate
  43. Swift-BAT detection of GRB 050401
  44. GRB 050401: Prompt XRT position
  45. Retraction of three Swift GRB triggers
  46. Swift-BAT detection of GRB 050331b
  47. GRB 050331: Swift UVOT Source
  48. Swift-BAT detection of GRB 050331
  49. GRB 050331: Swift XRT Position
  50. Swift Data Publicly Available Starting April 5, 2005
  51. Konus-Wind observation of GRB 050326
  52. GRB050326: optical limit
  53. GRB 050326: Early observations with Swift-UVOT
  54. GRB 050326 XMM-Newton observation
  55. GRB 050326 : Planned XMM-Newton observation
  56. GRB 050326: Swift XRT Position
  57. GRB050326: optical limit 33min before GRB
  58. GRB 050326 BAT refined analysis
  59. GRB050326: delayed XRT observation
  60. Swift-BAT detection of a bright GRB 050326
  61. GRB050319, optical observations
  62. GRB050319, color indices
  63. GRB050319: RTT150 Optical Observations
  64. Swift-BAT detection of a bright outburst from SGR1806-20
  65. Swift-BAT trigger 112060 is not a real GRB
  66. GRB 050319: ROTSE-III Refined Analysis
  67. GRB 050318: Swift-BAT refined analysis
  68. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  69. GRB 050319 R band observations
  70. GRB 050319: Swift-UVOT detection of the afterglow
  71. GRB 050315: Variability Analysis of Swift BAT Time History
  72. GRB050319: BR optical photometry
  73. GRB 050318: SWIFT-UVOT refined analysis
  74. GRB 050319: Swift-BAT refined analysis
  75. GRB050319,optical observation
  76. Swift Detection of GRB 050319
  77. GRB 050319: Detection of Possible Optical Counterpart
  78. GRB 050318: Swift/UVOT detection of afterglow emission
  79. GRB050318: Swift XRT position
  80. Swift-BAT detection of GRB 050318
  81. GRB050223: analysis of the XMM-Newton observation
  82. GRB 050306: ROTSE-III early limits
  83. GRB 050315: Swift-BAT further refined analysis
  84. GRB050315: Swift-BAT Refined analysis
  85. Non-detection of GRB050315 in ATCA Radio Observations
  86. GRB 050315: Swift XRT Position
  87. GRB 050315: Early Observations with Swift/UVOT
  88. Swift-BAT detection of GRB 050315
  89. GRB050223: No XMM-Newton OM detection of afterglow emission
  90. GRB050309: CONCAM pre-trigger and trigger coincident optical
  91. GRB 050126: Redshift determination
  92. Swift-BAT trigger 107873: No Swift XRT counterpart
  93. GRB 050306: Confirmation of X-ray afterglow
  94. GRB 050309, Early optical limits from RAPTOR
  95. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  96. GRB 050309 : Lulin R-band observation
  97. Swift 107873: P60 Optical Observations
  98. GRB 050306: CORRECTION to date of observation
  99. GRB 050306: No Swift UVOT Optical Counterpart Detected
  100. GRB 050306: Possible X-ray Afterglow Position from the Swift

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